1. Field of the Invention
This invention resides broadly in the field of electronic musical instruments and is particularly adaptable for use in instruments employing a time-division multiplexed signal for calling forth desired tones from those available in the instrument. The principles of the present invention are applicable to any digital electronic musical instrument in which musical sounds are generated in response to the actuation of key switches regardless of whether those switches are actuated directly, e.g. by the musician's fingers, or indirectly, e.g. by the plucking of strings. The term key is used in a generic sense to include depressible levers, actuable on-off switches, touch or proximity responsive devices, closable apertures and so forth. More particularly, the present invention relates to timbre modulation for electronic musical instruments.
2. Description of the Prior Art
Prior art attempts to simulate the transient voice effects of musical timbre have included the momentary sounding of independent "chiff" tones. As a result, the chiff or transient voice effect took on an independent character with limited dependence on the particular voices selected. U.S. Pat. No. 3,740,450 discloses a "chiff" of this type.
Prior art U.S. Pat. Nos. 3,908,504 and 3,972,259, while disclosing harmonic modulation and pulse width modulation respectively, employ complex and expensive hardware. The inventor knows of no prior art which affords the versatility and cost effectiveness of the present invention.